Conventionally, as a technology for detecting a target object, such as a person, a bicycle, or a motorcycle, present in the vicinity of a vehicle, for example, a technology in which image recognition is performed on an input image captured by a camera, through use of a recognition dictionary in which reference patterns of target objects are described is known.
For example, PTL 1 describes a technology in which a human candidate image is extracted through comparison of a captured image from a camera and a reference pattern indicating a luminance distribution for humans. In addition, as a method for acquiring the area of a target object within an image, in addition to image recognition such as that described above, there is an operation in which information indicating what is captured in the image is added by human operation, and information indicating the area of the target object being attached by human intent can be given.